Condenser attachment



Feb. 21, 1928.

G. E. WHITING CONDENSER ATTACHMENT Fi led Sept. 18. 1926 LWENTOR A T TORNE 3 Patented Feb. 21, 1928 I Y v UNITED STATES i,65t,755 PATENT. OFFICE].

GEORGE E. .WHITING, F BROOKLYN, NEW YORK;

connmvsnn ATTACHMENT.

.Applicationfiled September 1a, 1926. .Serial 110 136,323,

This invention relates to condensers for use in Wlreless, radio and other electrical circuits and apphances.

A particular object of the invention is to I combine with a variable condenser, a supplementary condenser of the fixed variety, the aim being to supply a supplementary condenser of fixed variety to a variable condenser of comparatively small capacity, the supplementary condenser representing the bulk of the capacity required in the combination, except when the total capacity required is very small, in which case, the capacity of the fixed unit in the combined instrurnent might be smaller than that of the variableunit to which. it is coupled.

A further particular object of the invenvariable condenser ismade variable within all practical or necessary limits by the addition thereto of a fixed condenser ofsuitable capacity. e

p To enable others skilled in the art to fully comprehend the underlying features of same in the various modifications in structure and relation contemplated, a drawing depicting a preferred form has been annexed as apart of this disclosure and in such drawings, similar reference characters denote corresponding parts throughout all the views, of which, 4

Figure 1 is a view in: sectional elevation showing the variable condenserhaving secured thereto a fixed condenser, the connection forming the main essential of my invention.

Figure 2 is a rear view in elevation of the variable condenser showing the arrangement thereon of the fixed condenser.

' Figure 3 is a sectional view in detail taken on the line 3 -3 of Figure 2, showing the connection post which secures the fixed con-- denser to the variable condenser.

Figure 4 is a fragmentary view of the my invention that they may embody the variable condenser showing in connection therewith, a means for holding a condenser ofthe fixedtype. I a

Figure 5 is an end view of the fixed condenser shown in Figure 4 and its method of connection to the variable condenser.

Figure 6 is a view similar to Figures showing a modified form of attaching a condenser cartridge to the variable condenser. Figure 7 is a view in side elevation of the cartridge type ofcondenser showing the'construction of the ends thereof which are adapted to engage the variable condenser.-

Figure 8 is a View similar to Figure'fi showing a still further modified form of fixed condenser holding device, and

Figure 9 is a view in perspective of one of the holding plates arranged in connection with the variable condenser to maintain the fixed cartridge condenser in its place.

Variable condensers have been made heretofore, consisting of alternate plates of metal, some of which are fixed and some of which are movable; Where small electric capacity is desired in the variable condenser,

the condenser itself may be kept small in 7 size and weight, but where a moderate capacity is necessary, the variable condenser becomes both heavy and bulky, not to say costly. Condensers of the fixed variety, however, which are composed of thin metal plate bound together by suitable insulating means and carriedbetween two end metallic binders, are small in weight, bulk. and cost and can be made up without increasing the bulk or weight, to any capacity desired.

If a small capacity variable condenser is always. used with a fixed capacity condenser attached thereto in parallel, the" mean ca pacity required for the circuit or work in hand can be obtained by selecting a suitable component of the fixed variety; and a' small variable condensercoupled thereto will always give the fine adjustment required for precision of effect in working. It is common knowledge that two fixed condensers placed in parallel have a capacity equal to the sum of'their respective capacities and such use has often been made of fixed condensers by both amateurs of ability and others but I propose to alter the value of a variable condenser by the addition of a fixed condenser and the rendering of this, a Per manent possibility with facility in operating by provision of suitable fittings and fixed condensers suitably made for such use, thus enabling an immediate change to be made in the total capacity of the combined condenser by the simple removal of one fixed condenser and the substitution ofanother or smaller or greater capacity, as desired.

Variable condensers, at present, are only variable up to their nominal greatest capacity, but my invention makes them absolutely variable Within all practical or necessary limits. 7

Referring to the drawings, and particularly Figures 1 and 2, it will be noted that i have provided, in connection with the usual variable condenser, which comprises the dial 5, back and front boards or panels 6 and 7 and fixed and movable plates 8 and 9 respectively, the latter being carried upon a suitable rotor 10 and the fixedplate being carried on suitable bolts 11, one of the bolts 11 and the rotor 10 being in electrical circuit as shown by the connector strips 12, which are secured at their ends, one to the rotor shaft 10 and the other to one of the fixed plate carrying bolts 11, these connectors 12 are positioned on the rear panel 7 and, as shown in Figure 2, are joined at their ends by a fixed condenser 13, which is made up of any suitable dielectric material positioned between suitable metallic bands or strips as is common in the construction of fixed condensers oi": the cartridge type. The ends 01 the connectors are positioned between the bottom end of the clips 14: and the panel 7. The clips being held in position through the medium of the suitable screws 15 and one of these clips 14 being positioned at each of the ends of the connectors so that when a fixed condenser is positioned in the ends of the clips, an electrical circuit is formed through the fixed condenser and also through the variable condenser.

The method of holding the fixed condenser in position is particularly the substance of my invention and in Figure 3, the clip let is composed of a bifurcated, upstanding piece of metal, the bifurcated portion of which formsspring jaws into which the fins, "formed on the ends of the fixed cartridges are held, to securely position the fixed cartridge in position in circuit with the variable condenser.

In Figure 4, I have shown a different type of holding means which consists in providing one of the fixed bolts 11 of the variable condenser with an extended threaded por tion 17, which is adapted to engage the interiorily threaded end of a sleeve 18 which acts as a .nut to grip the connector strip 12 between it and the panel 7 The cartridge in this instanceis provided with end fins 16 in which is formed eyelets, the eyelets carrying therein the beaded ends of the clip members 17, which are formed with yieldable jaws 18, which have a tendency to expand outwardly to engage the inner walls of the flanged sleeve member 19 which is held. in

position against the panel 7 through the medium of the nut 20, the latter also acting to retain the connector 12 about the sleeve 19 and against the panel 7;

in Figure 6, I have shown a still further modified form of connecting the fixed'condenser cartridge to the fixed and variable condenser post and as shown, the en'dof the fixed post 11 is extended and slotted seat 21 to provide spring. jaws which are adapted to pass through the eyelet 21 formed inth'e fin 16 on the end of the cartridge condenser 13. These eyelets are provided in the fins on either end of the cartridge and the rotor shaft of the variable condenser is extended the variable condenser rotor 10 is housed a suitable sleeve 23 over which is threaded a nut 24 to retain the connector 12 in position. It is of course understood'that these capacity of the circuit. u

in Figure 8,1 have shown an additional modification which consists in extending tl'ie connectors are the medium of bringing the circuit into the condenser and varying the fixed condenser post 11' and threading the same beyond the panel 7' to receive the nut 25, the nut holding in place the connector 12 and also a substantially L-shaped bracket 26, in the outer end of which is-provided' an opening 27 to receive the nose-like end 28 of the fixed cartridge condenser 29.. The opposite end of the condenser is held in a similar bracket 26, the inner end of which "is provided with an opening through which passes a threaded sleeve 30, the nut 31 being threaded over the sleeve to hold the bracket 26 in place and also the usual connectors 12. it is evident therefore, that the upstanding portions of the brackets 26 can be made of spring metal so that the nose-like end 28 of the cartridge condenser 29 will spread thecost of the electrical fixture, as a whole, of

condenser and the rendering of this combination with a minimum of time, labor'and number of parts necessary.

While I have illustrated and described my invention with some degree of particularity, I realize that in practice various alterations therein may be made. I therefore reserve the right and privilege of changing the form of the details ofconstruction or otherwise altering the arrangement of the correlated parts without departing from the spirit of the invention or the scope of the appended claims. w

Having thus described my invention what I claim as new and desire to secure by United States Letters Patent is 1. The combination with a variable condenser of a fixed condenser, the variable condenser havmg a panel, retaining extensions on said panel, and the fixed condenser being arranged to be releasably held in said retaming extensions, and means for completmg a circuit through the variable and fixed condenser.

2. In combination, a variable condenser members for holding said plates, sleeves associated with said 0st members, a fixed condenser provided with resilient sleeve engaging extensions whereby the fixed condenser can be releasably secured to said sleeves.

3. The combination with a variable condenser of a fixed condenser, and gripping extensions on said variable condenser for releasably holding the fixed condenser in position and means for completing a circuit through both thefixed and variable con- I densers.

4. The combination with a panel of a variable condenser of a plurality of yieldable re'- taining members, a fixed condenser, and eye lets on the ends of said fixed condenser for releasably engaging said retaining members. I

5. In electrical condensers, the comb-ination with a variable condenser having a plurality of fixed and movable plates, posts supporting said fixed and movable plates, and insulating members carrying said posts, of a plurality of yieldably holding arms carried by one of theinsulat-ing members and holding sleeves adjacent said posts ;for receiving the holding arms whereby the fixed condenser is releasably held in position on said variable condenser. V

In testimony whereof I afiix my signature. 

